A dome type camera is, for example, used for surveillance of a facility and installed on a wall, ceiling, or the like of a facility. Such a dome type camera has a camera for shooting in a prescribed shooting direction, a chassis (case) to be attached with the camera, and a dome type cover for covering the camera attached to the chassis. The cover of the dome type camera is provided with a window where the cover is cut corresponding to the angle of view of the camera so that the field of view of the camera in a shooting direction may be maintained and other parts may be protected so as not to be seen from the outside. For this reason, when such a dome type camera is installed on a ceiling, wall, or the like of a facility, an adjustment work is required which matches the shooting direction of the camera and the orientation of the window of the cover.
Conventionally, a dome type camera is known in which each of the chassis and the cover has a scale marked thereon that corresponds to each other. In the conventional dome type camera, when it is installed on a ceiling, wall, or the like of a facility, the shooting direction of the camera and the orientation of the window of the cover are matched by aligning the scales of the chassis and cover with each other. Such a dome type camera is disclosed, for example, in Japanese Patent Laid-Open Application No. 2004-356669 (pages 4 to 10 and FIG. 2).
However, the conventional dome type camera requires that when it is installed on a ceiling, wall, or the like of a facility, the scales of the chassis and cover be aligned with each other in advance before the cover is attached to the chassis. The cover is temporarily attached to the chassis and the installation of the dome type camera is completed; and then if a situation arises in which the orientation of the window of the cover requires to be matched to the shooting direction of the camera, the cover has to be detached from the chassis, and the scales of the chassis and cover have to be aligned with each other again. For example, if a worker has misread the scale, or if the orientation of the cover has been changed by external forces such as an earthquake and tampering, the cover has to be detached from the chassis, and the scales of the chassis and cover have to be aligned with each other again. So, readjusting the orientation of the window of the cover would require time and effort.